Three annual reports on HIV and sexually transmitted infections in Australia released this week show a rise in HIV diagnoses. The reports were released at the Australasian HIV/AIDS Conference 2012 currently taking place in Melbourne.

The reports show that new diagnoses of HIV in Australia have risen 50% over the past 10 years. Also, an eight percent spike in HIV diagnoses occurred in 2011, when 1137 Australians were diagnosed with the virus.

“It remains critical to continue to invest in effective programs and campaigns to reinforce condom use and inform men of the appropriate use of other sexual risk reduction practices, such as limiting condom-less sex to partners of the same HIV status,” said John de Wit, University of New South Wales professor and lead editor of the Annual Report of Trends in Behaviour 2012.

The trends show that unprotected anal intercourse with casual partners among gay men has also increased over the past decade. In 2011, 34.6% of Australian men who had sex with a casual partner reported having unprotected anal intercourse in the past six months.

However, David Wilson, UNSW associate professor and head of the Surveillance and Evaluation Program for Public Health at the Kirby Institute, stated that part of rise in HIV diagnoses could be due to better testing trends for Australians who are at risk for HIV.

“We believe that between 20 and 30 per cent of HIV cases in Australia remain undiagnosed and that earlier diagnosis among these people and initiation of antiretroviral therapy would have large health benefits for the individual and reduce new infections in the community,” said Wilson.

The reports also revealed the trends in the prevalence of sexually transmitted infections in Australia. Gonorrhoea and chlamydia infections are on the rise, especially among remote indigenous communities. However, the rates of genital warts are on the decline due to the availability of the HPV vaccine.